Tracheoesophageal Fistula (TEF)

Tracheoesophageal fistula is an abnormal connection between the trachea and esophagus. It occurs in approximately 1 in 4,000 births. Currently, an overall survival of 85% to 90% has been reported from developed countries. In developing countries, however, several factors contribute to higher mortality rates. Such factors include prematurity, delay in diagnosis with an increased incidence of aspiration pneumonia, and a shortage of qualified nurses.

Tracheoesophageal fistula (TEF) is a condition in which an abnormal channel, called a fistula, connects the windpipe (trachea) to the tube that leads from the mouth to the stomach (esophagus). Food and saliva can get into the trachea and lungs through this channel. This can make a child cough or choke and lead to lung infections or pneumonia.

Pathophysiology:

1. Cause is unknown in most cases. Possible influences include:

• inheritable genetic factors
• possible chromosomal (structural) abnormalities including trisomy 3p, partial deletion 5p, distal 13q deletion, interstitial deletion of 17q.
• teratogenic stimuli, such as the anti-cancer drug adriamycin and diethylstilbestrol (DES)

2. Failure of proper separation of the embryonic channel into the esophagus and trachea occuring during the fourth and fifth week of festation.

Types of esophageal atresia: esophageal atresia and tracheoesophageal fistula.

• Type I (Type A): proximal and distal segments of esophagus are blind; there is no connection to the trachea; accounts for approximately 7% of cases; second most common.
• Type II (Type B): proximal segments of esophagus opens into trachea by fistula; distal segment is blind; rare, 0.8% in most cases.
• Type III (Type C): proximal segments of esophagus has blind end; distal segment of esophagus connects into trachea by fistula; most common, with 86% of cases.
• Type IV (Type D): esophageal atresia with fistula between proximal and distal ends od trachea and esophagus (rare, 0.7% cases).
• Type V (Type E): proximal and distal segments of esophagus open into trachea by fistula; no esophageal atresia but sometimes referred to as an H-type fistula; occurs in 4.2% of cases; not usually diagnosed at birth.

Clinical Manifestations:
These appear soon after birth.

• Excessive secretions.
• Constant drooling
• Large amount of secretions from nose
• Saliva or formula accumulates in upper esophageal pouch and is aspirated into airway

• Intermittent, unexplained cyanosis and laryngospasm.
• Caused by aspiration of accumulated saliva in blind pouch
• Gastric acid is regurgitated through distal fistula
• Abdominal distention.
• Occurs as a result of air entering the lower esophagus through fistula and passing into stomach, especially when the child is crying.
• Violent response after first or second swallow of feeding.
• Infant coughs and chokes
• Fluid returns through nose and mouth
• Cyanosis occurs
• Infants struggles
• Poor feeding.
• Inability to pass catheter through nose or mount into stomach; tip of catheter stops at blind pouch, or atresia. Note: Be aware of coiling of catheter; coling may make catheter appear to be descending into stomach.
• Infant can be premature, and pregnancy complicated by polyhydramnios.

Diagnostic Evaluation:

• Ultrasound scanning techniques enable TEF to be identified in utero for some infants.
• Failure to pass a 10F catheter (smaller catheters may coil) into the stomach through nose or mouth. Catheter is left in situ while an X-ray confirms the diagnostic.
• pH of tracheal secretions is acidic.
• Flat plate X-ray of abdomen and chest may reveal presence of gas in stomach and catheter may coiled in the blind pouch. Barium X-ray may be used in some cases.
• Electrocardiogram and echocardiogram are performed because there is a high association with cardiac anomalies.